Scientists confirm new virus as cause of SARS

Scientists have confirmed the identity of the virus which causes severe acute respiratory syndrome (SARS), a lethal new disease first detected in Asia, the World Health Organisation said yesterday.

In experiments conducted at Erasmus University in Rotterdam, the Netherlands, scientists infected monkeys with the coronavirus suspected of causing SARS and found that the animals developed the same symptoms of the disease that humans do.

The test was a crucial step in verifying the cause of the disease, which has so far made at least 3235 people ill in 22 countries and killed 161 people worldwide, mostly in China and Hong Kong.

Scientists had been almost certain that the new form of coronavirus first isolated from sick patients on March 27 by the University of Hong Kong was the cause of SARS.

But they could not say for sure until they had satisfied what is known as the Koch's postulates - four scientific tests that verify whether a bug causes a certain disease.

"The Koch's postulates have been fulfilled, so we can now say for certain that the new coronavirus is the cause of SARS," said Dr Klaus Stohr, a World Health Organisation virologist who participated in a conference in Geneva, Switzerland.

Researchers at the University of Hong Kong said a new genetic sequencing of the SARS virus proves conclusively that it came from animals.

But, the virus is nonetheless "something that is new to science", said Malik Peiris, a microbiologist at the university, before the WHO findings were announced.

Asked about the possibility that the virus was man-made, he said there was no chance of that.

"That whole genome is essentially new," he said. "Nature has been the terrorist throwing up this virus."

Researchers at a Singapore government-run institute are reportedly almost ready to begin trials of a test to detect the presence of SARS in a patient's blood before the onset of symptoms.

University of Hong Kong researchers said they believed - but had not proven - that the virus mutated into a more dangerous form that infected about 300 people in one hard-hit apartment complex.

"This virus did not originally exist in humans, it definitely comes from animals," said Yuen Kwok-yung, a microbiologist at the University of Hong Kong.

"But what this is telling us is that in fact, this virus is not close to any of the known human or animal viruses," Peiris said. "It is something that is new to science."